UNITED STATES DEPARTMENT OF AGRICULTURE 

• , BULLETIN No. 322 

Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 


Washington, D. C. PROFESSIONAL PAPER. January 7, 1916 


UTILIZATION OF AMERICAN FLAX STRAW IN THE 
PAPER AND FIBER-BOARD INDUSTRY. 

By Jason L. Merrill, Paper-Plant Chemist, Paper-Plant Investigations^ 


CONTENTS. 


Page. 


Introduction_ 1 

Migration of the flax crop_ 3 

Flax straw in the paper and fiber- 

board industry_ 4 


Page. 

Flax tow in the fiber-board in¬ 


dustry _ 16 

Suggestions for flax farmers_ 22 

Conclusions_ 23 


INTRODUCTION. 

The purpose of this paper is to report recent tests on the utilization 
of American seed-flax straw in the paper and fiber-board industry. 
Successful commercial tests have been completed, wherein domestic 
flax straw and tow were used in place of imported flax waste in the 
manufacture of fiber counter boards, Avhich are employed to a great 
and increasing extent in making toe boxes and counters for shoes. 
The boards made during these tests were pronounced satisfactory by 
manufacturers and were sold to the trade at the regular price for 
such boards. 

From an economic point of vieiv it seems inconsistent that this 
country should import flax waste from foreign countries for paper 
and board manufacture and at the same time actually burn one and 
one-half million tons of flax straw which is raised within its own 
borders. The reason usually given and naturally assumed is that it 
is more profitable to use the foreign article or that the domestic ma¬ 
terial is not suitable for the purpose. It will be shown in this report 
that these reasons have not been well founded. 

1 The work of investigating flax straw as a paper-making material was initiated by 
Mr. Charles J. Brand, now Chief of the Office of Markets and Rural Organization, when 
he was Physiologist in Charge of Paper-Plant Investigations of this bureau. Mr. Brand 
still retains supervision of this line of the bureau’s activities. 

Note.—T his bulletin gives an account of recent work on the utilization of American 
seed-flax straw in the paper and fiber-board industry and will be of interest to chemists, 
flax farmers, counter-board manufacturers, and paper makers in general. 

8957°—Bull. 322-16- 


1 























2 BULLETIN 322, U. S. DEPARTMENT OF AGRICULTURE. 

Among other reasons why flax straw should be investigated as to 
its paper value there should be cited the present condition and tend¬ 
ency of our rag paper-stock supply, which would welcome new 
sources of material at this time. About 70 per cent of the rags 
used in paper manufacture in the United States are imported from 
European countries. It is well known that very good writing papers 
have been produced from flax straw’, but the cost of the processes em¬ 
ployed up to the present time has not been justified by the quality 
and value of the product. 

The rope-paper and high-grade sack-paper manufacturers also 
have been consuming an immense quantity of foreign raw material, in 
spite of the fact that it is known that American flax straw is capable 
of being used for some of these purposes. But here again the product 
has not justified the cost of the process. Manufacturers of cartridge 
or shot shell papers annually import approximately 2,000 tons of 
flax waste for the production of their paper, and the question of a 
satisfactory substitute is engaging their attention. From the paper 
maker’s point of view’, therefore, the flax crop represents a raw 
material of immense latent value, and, as will be shown, it is likewise 
a source of great latent value to the flax farmer. 

Certain promoters have made attempts to exploit this material, 
but their efforts often have been based upon insufficient evidence and 
data. It is the object of this paper to show to wdiat extent flax straw’ 
may be utilized in the paper-making and fiber-board industries and 
to suggest further possibilities. 

One of our most highly prized and valued oils and one for which 
no satisfactory substitute has been found is linseed oil, which is 
manufactured solely from the seed of the common flax plant {Linum 
usitatissinhum). The raising of flax is an industry of great im¬ 
portance, as is shown by the fact that the United States normally^ 
has about 2,200,000 acres devoted to its culture, w’hich produce 
about 20,000,000 bushels of seed, valued at approximately $33,000,- 
000. This seed flax of the Northwest is different in type from that 
cultivated primarily for fiber production, and because of this dif¬ 
ference and the methods of cultivating and handling the crop the 
straw can not be made to produce a good spinning fiber. 

The straw resulting from the harvesting and thrashing of this 
crop usually is burned, not because it has no intrinsic value, but 
because no adequate industrial use has been established to absorb it. 
With a production of three-fourths of a ton of straw per acre, the 
total annual tonnage of straw amounts to approximately 1,600,000 
tons, of Avhich not more than 200,000 tons are at present put to any 
profitable use. 

1 Five-year average, 1909 to 1913. 



D. of D. 

JAN 14 1916 



UTILIZATION OF AMERICAN FLAX STRAW. 3 * 

The utilization of the remaining 1,400,000 tons would be of im¬ 
mense economic importance, since (1) its paper-producing possi¬ 
bilities are equal to the annual production of wrapping paper and 
more than double the annual production of writing paper in theUnited 
States; (2) its sale would represent an added revenue to the farmers 
of about $5,000,000 annually; (3) it would exert a very strong 
tendency toward maintaining the flax crop in our agricultural 
system; (4) it probably would result in the establishment of paper- 
manufacturing industries in sections where there are none; (5) 
it would aid in making our paper industry more independent of 
foreign raw paper-making materials; and (6) it would produce a 
keener realization of the latent value of some of our enormous crop 
wastes. 

MIGRATION OF THE FLAX CROP. 

The acreage of the flax crop has not remained permanent in any 
one section, and it is this constant migration which is of as vital 
importance as is its total available tonnage. 

The total crop is variable in acreage and yield to the extent shown 
by Table I. 

Table I. — Acreage and yield of the flax crop in the United States for 1899, 1902, 
and from 1909 to 19Iff, inclusive. 


Year. 

Acres. 

Bushels of 

1 seed. 

i 

Year. 

Acres. 

Bushels of 
seed. 

1899 . 

2,110,000 
3,740,000 
2,083,000 
2,467,000 

19,979,000 
29,285,000 
19,512,000 
12,718,000 

1911. 

2,757,000 

2,851,000 

2,291,000 

1,885,000 

19,370,000 
28,073,000 
17,853,000 
15,559,000 

1902. 

1912. 

1909.. 

1913. 

1910. 

1914. 




During its entire history flax has been a pioneer crop, being 
used as a first crop on the upturned virgin soil. This soil is 
claimed to be too rich for corn and other cereals, but, on account 
of the very meager root system of the flax plant, it thrives here at 
its best. Flax does not do as well on the same land until after other 
crops have been raised and the land put into grass again, when it is 
ready to be broken up for a new flax seed bed. The old prevalent 
idea that the flax crop is very exhausting to soil fertility has been 
shown to be a fallacy,^ and it has been proved that it does not tax 
the soil fertility as much as either wheat or oats. 

Table II gives statistics of flax acreage which show the migration 
of the crop in certain States since 1899. 

1 Bolley, IT. L. Flax culture. N. Dak. Agrr. Exp. Sta. Press Bull. 46, 4 p., 3 figs. 
1911. 

Bull, C. P. Flax growing. Minn. Farmers’ Libr. Ext. Bui. 27, 8 p., illus. 1912. 






















4 


BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 


Table II. — Area devoted to flax in certain States in 1899, 1909, and 1913, 
shoiving the migration of the crop. 


state. 

1899 

1909 

1913 

State. 

1899 

1909 

1913 

Ohio. 

Acres. 
3,092 
394 
192,167 
7,652 
883 
11,263 

Acres. 

552 

115 

45,014 

2,934 

261 

9,423 

Acres. 

Iowa. 

Acres. 
126,453 
566,800 
774,000 
302,010 
16 

Acres. 
15,549 
358,426 
1,068,049 
518,566 
37,647 

Acres. 
28,000 
.350,000 
1,000,000 
425,000 
400,000 

Illinois. 

Kansas. 

Nebraska. 

Michigan. 

Wisconsin. 

60,000 
9,000 

9,000 

Minnesota. 

North Dakota. 

South Dakota. 

Montana. 


In 1879 Illinois, Iowa, and Indiana were the leading flax States. 
From present indications Montana is forging ahead very rapidly as 
a leading flax State, and Kansas and Nebraska also are becoming 
larger producers. 

Since North Dakota is the largest flax State, the effect of migration 
in that State since 1902 has been determined. A north and south line 
of counties in the extreme eastern end of the State and a similar 
line of counties in the extreme western end have been chosen for 
comparison (Table III), to show the effect of migration. 


Table III.— At'ea devoted to flax in the eastern and. icestern sections of North 
Dakota, in certain years, shoiving the westward migration of the crop. 


Year. 

Number of acres in 
flax. 

Percentage of total 
flax acreage of the 
State. 

Eastern 

coimties. 

Western 

coimties. 

Eastern 

counties. 

Western 

counties. 

1902. 

892,000 
498,800 
267,000 
188,240 

145,400 
208,090 
404,200 
325,700 

47.0 

42.3 

23.6 

26.7 

7.6 

17.6 

35.7 
46.2 

1905. 

1910. 

1914. 



The figures in Table III show very clearly that the crop has mi¬ 
grated westward across the State and that in twelve years the eastern 
and western sections have changed places in relation to the total flax 
crop of the State. It naturally might be inferred that the crop will 
migrate eventually entirely out of the State, but, because of the short 
distance to the Rocky Mountain region and the Canadian line and 
because of increased knowledge of successful flax raising, it seems 
ver}^ probable that flax will continue to be an important crop in this 
State and region for a considerable period. 

FLAX STRAW IN THE PAPER AND FIBER-BOARD INDUSTRY. 

UTILIZATION OF FLAX STRAW IN THE PAPER INDUSTRY. 

There is a great diversity of opinion as to the possibility of 
economically manufacturing paper from flax straw, but there is an 
almost unanimous agreement that it contains a certain proportion of 









































UTILIZATION OF AMERICAN FLAX STRAW. 


5 


fiber which would be of value could it be separated economically 
from the straw. Different requirements are made of a raw material, 
however, depending on the grade of product desired. It might, for 
example, meet the requirements of the board manufacturer in regard 
to product and cost and not be capable of interesting the writing- 
paper or wrapping-paper manufacturer, for reasons of product or 
cost, or both. It may be found also that the straw can be used in only 
one or two grades of product, as is the case with poplar wood and 
esparto grass. 

Much work has been done by different experimenters in testing this 
straw for its paper value, and samples of writing and sack papers 
have been produced which, so far as quality is concerned, seem to be 
satisfactory. A small flax-tow mill is in operation in North Dakota, 
which is equipped with a pulping boiler, beater, and other apparatus, 
and it has produced bleached flax pulp of an apparently satisfactory 
quality, from which good grades of writing paper have been manu¬ 
factured. But the work, although promising, is yet in the experi¬ 
mental stage. 

In 1908 the Bureau of Plant Industry, cooperating with the United 
States Forest Service, conducted a number of pulp-making tests with 
the straw and found that a very severe chemical action was required 
and that it was impossible to bleach the pulp economically with 
ordinary bleaching-powder solutions. 

In spite of all the activity in this direction, however, no industry 
has been established whereby paper manufacturers have been enabled 
to utilize this immense and valuable crop waste. 

UTILIZATION OF FLAX STRAW IN THE FIBER-BOARD INDUSTRY. 

In the manufacture of certain grades of fiber board known as 
counter board, one of the main constituents is flax waste from the tex¬ 
tile industries of Europe. The total quantity so used in this country 
is approximately 7,000 tons per annum. This waste is divided into 
four distinct classes, namely, flax card waste, flax card strippings, 
flax rove waste, and flax washed waste, depending on the particular 
operation from which each is derived. These wastes, with the excep¬ 
tion of the washed waste, have a certain amount of flax wood shives 
associated with them, the card waste containing the most and the rove 
waste the least. The washed waste contains no shives and is the 
highest priced; likewise, the least used in board manufacture. 

As to the possibility of substituting domestic flax straw for the im¬ 
ported flax waste, a comparison from a chemical and physical stand¬ 
point brings out the following facts: 

(1) Flax waste is derived from retted flax straw and consequently 
contains very little of the mucilaginous pectin compounds, such as 


6 


BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 


are present in domestic nnretted flax straw. For this reason alone 
flax straw would require the use of more chemicals in its reduction 
than does flax waste. 

(2) The proportion of wood in flax straw is far higher than in flax 
waste, which probably would necessitate a higher consumption of 
chemicals in treating the former. If it should appear necessary to 
exclude wood shives from the finished product, it might be found 
necessary to reduce the Avood to a greater extent than when using 
flax AA^aste, in AA^hich case the reduction might require the employ¬ 
ment of a higher steam pressure or a longer time of treatment, or 
both. 

The greatest difference in a physical sense betAA^een straAA’ and 
Avaste is that the former, being composed of lengths of the Avhole 
stalk, presents larger pieces, or masses, to the action of the chemi¬ 
cals, thus necessitating the employment of more time in the chemical 
reduction process. These chemical and physical differences, hoAV- 
eA^er, do not differ in kind but only in degree, from Avhich it AAmuld be 
concluded that the method found to be satisfactory Avith straw would 
differ in no fundamental manner from that knoAAm to be satisfactory 
Avith AA^aste. 

LABORATORY EXPERIMENTAL TESTS ON THE PREPARATION OF PULP. 

In March, 1914, preliminary Avork AA^as started by the Department 
of Agriculture on the utilization of flax straAA^ as a raAA^ material for 
sack or wrapping paper manufacture. It Avas decided that, of all the 
fiber-treating processes, the milk-of-lime process Avas the most Avorthy 
of trial, after the folloAAung factors, among others, had been con¬ 
sidered carefully: 

Lower initial cost of factory installation. —On account of freight rates, AA^liich 
figure so prominently in the final costs of manufactured products, and because 
of the remoteness of the flax region from paper mills, it might appear advisable 
to establish pulp or paper mills nearer the source of raw-material supply. It 
Avould be inadvisable to install a process which demands a heaA’y expenditure 
per ton, such as the soda, sulphate, and sulphite processes, before the true 
value of the material Avere proved by actual manufacture for a reasonable 
period of time. Such a practical test might be prohibitive because of the 
shipping cost for such a distance, and few, if any, manufacturers could be 
expected to operate at a loss or even at a low profit for a sufficient period to 
determine the advisability of factory installation. The same remarks apply 
to the milk-of-lime process, but not to the same degree. 

Tensile strength of the fibers preserved. —As is commonly known, caustic soda 
pulping loAvers the tensile strength of fibers more than the milder milk-of-lime 
process. 

Class of employees required. —The milk-of-lime process does not demand the 
employment of as large a staff or as great a variety of skilled help as the soda, 
sulphite, or sulphate processes. 


UTILIZATION OF AMERICAN FLAX STRAW. 


7 


The laboratory work consisted of pulping tests, beating and wash¬ 
ing the pulp and making it into hand sheets. From the data gathered 
during this process and from the samples conclusions were drawn 
as to procedure and conditions to be employed on subsequent semi¬ 
commercial tests. It is fully realized that in general it is impossible 
to duplicate commercial working conditions on a small laboratory 
scale; therefore, laboratory results, valuable as they may be, should 
be interpreted commercially only with extreme caution. The follow¬ 
ing laboratoiy work and results are regarded, therefore, as approxi¬ 
mate indications, to assist in subsecpient semicommercial tests. 

The flax straw used in these tests was of the ordinary seed-flax 
type raised in the vicinity of Fargo, N. Dak., was thrashed with the 
ordinary thrashing machine, as is the practice in that section, and 
was baled in an ordinary hay baler. The bales contained their proper 
complement of chaff, usually 30 per cent, and averaged SO pounds in 
weight. 

To serve as a fiber suitable for paper manufacture it is necessary 
to reduce the wood}^ portion by cooking or bleaching to such a condi¬ 
tion that the beater will be able to disintegrate mechanically or 
separate the wood}^ shives to such a size or condition that they may 
be removed from the true fiber by washing in the regular manner. 
The proportion of woody matter that it is necessary to remove de¬ 
pends naturally on the grade of product desired. 

I^ulping tests, technically known as “ bleaches,” were conducted in 
an iron rotary boiler of 10 gallons capacity, heated by means of direct 
steam and gas burners, and rotating 1 revolution per minute. 

In conducting a bleach, the boiler is charged full of straw, from 
which a sample has been drawn for a moisture determination, in 
order to calculate the weight of bone-dry straw employed. The pre¬ 
determined quantity of lime (burned lime), calculated in percentage 
of the bone-dry straw, is added in the form of milk of lime, together 
Avith sufficient Avater to amount to 1 gallon per 2^ pounds of straAv. 
After closing the boiler and rotating a feAv times, direct steam at 110 
pounds pressure is admitted, the gas urners underneath are lighted 
in order to counteract excessiA-e radiation, and the charge is heated to 
a certain point in one hour. 

The control of the degree of heat in a boiler is accomplished in 
practice by a steam-pressure gauge Avliich bears a direct relation to 
the temperature of the charge, but since it is not pressure but tem¬ 
perature Avhich induces the chemical actions, it Avould obviously be 
as correct to employ temperature as i)ressure for a guide. In all of 
the laboratory Avork the temperature control Avas used, being effected 
by a thermometer inserted in a horizontal Avell extending from the 
end of the boiler to the center of the charge. After the desired tern- 



8 BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 

perature has been reached this degree is maintained constantly for 
the required number of hours, after which the burners are removed 
and the boiler cooled in about half an hour by means of a small 
stream of water applied to the boiler shell. The resulting stock, on 
removal from the boiler and after remaining unwashed over night, 
is well washed with water, pressed into a uniform cake, weighed, and 
a sample drawn for a moisture determination, from which data the 
yield of total stock is determined. 

The stock after bleaching shows the bark more or less completely 
resolved and the bast very loosely held in the structure. The inside 
woody portion appears practically unchanged, but in reality it has 


Pig. 1.—Experimental 10-pouncl beater, supplied with washer. 

suffered a chemical and physical change whereby the structure is 
mechanically weakened. 

Xext, the stock is ‘‘ beaten ” in an experimental 10-pound beater 
(fig. 1), which consists of a trough in which the stock is caused to 
circulate and pass between a bedplate of coarse knives or bars and a 
series of similar knives set in tlie periphery of an iron roll making 
about 150 revolutions per minute. The distance between the two 
sets of knives can be regulated and altered to any degree, according 
to the effect desired. This action causes the bleached stock gradually 
to be distintegrated into its ultimate cells, the bark being reduced 
to bast cells and the small connecting cells of the structure and the 





UTILIZATION OF AMERICAN FLAX STRAW. 


9 


woody portion partly to very fine skives and partly to the ultimate 
wood cells. 

The ineasurements shown in Table IV give an idea of the 
kinds and relative sizes of the various cellular elements of which 
flax pulp is composed. The pulp in this case was obtained by the 
soda process, on account of the more complete separation of the cells 
in the pulp (fig. 2). 



Pig, 2.—Microphotograph of pulp from flax straw before the smaller cells are removed. 

(Magnified 103 diameters.) 

Table IY.— Dimensions of the cells of flax pulp. 


Dimensions (millimeters). 


Kind of cells. 

Length. 

Width. 

Ratio 

of 

length 

to 

width. 

Maxi¬ 

mum. 

Mini¬ 

mum. 

Aver¬ 

age. 

Maxi¬ 

mum. 

Mini¬ 

mum. 

Aver¬ 

age. 

Pith cells (from the central portion of the 








stalk). 

0.14 

0.08 

0.10 

0.08 

0.06 

0.00 

1. 5 

Epidermal cells. 

. 11 

.07 

.08 

.03 

.01 

.02 

4..3 

Short parenchyma cells. 

.13 

.09 

. 11 

.02 

.01 

.02 

7.2 

Long parenchyma cells. 

.40 

.18 

.29 

.04 

.02 

.03 

9.2 


(P 

(U 

(') 

.02 

.009 

.011 


Wood'fibers (from the woody portion of the 





stalk). 

. 420 

.10 

.20 

.013 

.009 

.011 

17.5- 

Bast fibers (the long fiber of the plant, which 








is of value 1 o the paper maker). 

64 

.5 


.039 

.010 

.019 



1 Extending throughout length of plant. 


S!)r)7°—liiill. R22—16- 



































10 


BULLETIN 322^ U. S. DEPARTMENT OP AGRICULTURE. 


llie short fibers or cells are not sufficiently long or correctly pro¬ 
portioned and shaped to possess the felting quality on which their 
value largely depends in paper manufacture; moreover, in distinc¬ 
tion from the long bast fiber, they are liquefied, which renders them 
very undesirable in the manufacture of durable products. 

The separation of the dirt and short fibers from the long true 
fibers was accomplished in the laboratory, as in practice, by means 
of a washer, which is a rotating drum covered with 20-mesh Avire 
cloth on the sides and having helical scoops inside connecting with 
a hollow trunnion. This Avasher is attached invariably to the beater 
and by being loAvered about one-third its breadth into the circulat¬ 
ing stock it removes water, dirt, and short fiber, Avhile fresh Avater is 
admitted at the other end of the beater. 



Fig. 3.—Paper-testing machines in a constant-humidity room. 


Obviously, this light beating and Avashing should be carried to 
different degrees, depending on the quality of the product desired. 
For example, a medium grade of fiber board Avould not require as 
much Avashing as one of higher grade and a stock suitable for Avrap- 
ping or sack paper would require a very complete Avashing. 

After having been Avashed to the desired degree, the stock is 
drained from the beater, pressed, Aveighed, and sampled for a mois¬ 
ture determination, in order to calculate the yield of the Avashed fiber. 
It is then returned to the beater, and the long true fiber is reduced 
to a degree Avhich is suitable for manufacture into a sheet of paper. 

All sheets Avere made Avaterleaf on a hand mold 5^ by 10 inches, 
dried on a steam-heated cylinder at 105° C. under a definite tension, 
and subsequently given physical tests under constant conditions of 
temperature and relatiA^e humidity. 

To shoAv the effect on the physical constants of a paper caused 
by drying the Avet handmade sheet under different tensions, the re- 








UTILIZATION OF AMERICAN FLAX STRAW. 


11 


suits of one series of tests on a lime-cooked flax-straw paper are 
here given (Table Y). The wet sheets were placed on a cloth- 
covered iron cylinder heated by steam to 103° C. and held down by 
placing on top a cloth which was maintained at a definite tension. 
The sheets shrank more and cockled more under a light tension than 
under an increased tension. The physical tests were made at 80° C. 
and 65 per cent relative humidity (fig. 3). 

Table V. —Effect on the physical constants of paper dried under different 

tensions. 


Tension of cloth. 

Breaking 
length 
of sheet 
(meters). 

Folding 
factor of 
sheet, 
ream 25 
by 40 by 
500. 

550 grams. 

3,165 

3,420 

3,810 

4,150 

3,960 

0.00312 

1,245 grams. 

.00407 

2,155 grams. 

.00487 

3,240 grams.,_ 

.00571 

3,700 grams.!_ 

.00405 



From Table Y it appears that within certain limits the strength 
and folding quality of a sheet depend to a considerable degree upon 
the method of drying. 

Bleaches were made with from 12 to 25 per cent of burned lime, 
calculated on the bone-dry weight of the straw used, employing 
temperatures from 135° to 170° C. and treating at the definite tem¬ 
perature from 6 to 10 hours. 

The most thorough reduction and generally satisfactory results 
were obtained with 14 per cent of lime acting for 10 hours at 170° C., 
or the equivalent of 100 pounds steam pressure. The yield of total 
fiber obtained did not vary much with the different bleaching condi¬ 
tions, ranging from 60 to 68 per cent of the bone-dry weight of the 
original straw employed. Determinations of the yield of washed 
or separated fiber on the satisfactory bleaches gave an average of 32 
per cent of the bone-dry weight of straw employed. 

MILL TESTS ON THE MANUFACTURE OF WRAPPING PAPER. 

Tests of wrapping paper from flax straw were made at Cumber¬ 
land Mills, Me. Semicommercial machines were used, and most of 
the work was performed by the regular mill employees. 

The straw used in these tests was raised in the vicinity of Fargo, 
N. Dak., being the same as that used in the laboratory tests. It was 
first sieved on a 4J-mesh screen, in order to remove the loose chaff 
composed of dirt, seeds, and empty seed capsules, which amounted 
in total to 24.5 per cent of the original straw. 















12 BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 

Chemical reduction was effected in a steel, rotary pulp boiler, 6 
feet long by 4 feet in diameter, which was supplied with a ther¬ 
mometer well, pressure gauge, and pipes for relief and direct steam 
inflow. 

Bleach No. 193 .—A charge of 277 pounds (242 pounds, bone-dry 
weight) was treated with 15 per cent of burned lime (36.4 pounds) 
and 100 gallons of water, the lime being slaked in part of the water 
before being added. Direct steam was admitted, so as to bring the 
charge up to 148° C., or 50 pounds steam pressure, in 1 hour; then 
regulated so as to maintain this pressure for 10 hours, after which 
the pressure was relieved and the contents removed. This stock was 
followed down with a fairl}^ light roll and washed for 3 hours in a 
400-pound beater, at which point the stock was removed, drained, 
pressed, weighed, and sampled for moisture content. From these 
data the yield was found to be 64.6 per cent of the sieved straw, or 
.48.7 per cent of the original bone-dry straw. 

Bleach No. 191 ^.—This bleach was made in the same manner as No. 
193 and beaten and washed 3 hours, after which the stock from No. 
193 was added to it in the beater. The combined stocks were beaten 
^ a total of 19 hours, the last 7 of which were fairly hard, the washer 
being used the first 4 hours. The long bast fibers were very strong 
and not easily reduced; likewise, the woody portion did not com¬ 
pletely reduce to the separated individual fibers, but remained as 
more or less fine shives, or cell aggregates. The washer used in this 
work was 60-mesh, while a much coarser, possibly 20 or 25 mesh, 
would have removed many more of the shives and given a far better 
product. This unsized and unscreened stock was pumped to the stuff 
idlest and run over a 30-inch Fourdrinier paper machine, in conjunc¬ 
tion with a Jordan type of refiner. The stock acted well on the ma¬ 
chine wire, was strong after the second press rolls, did not cockle on 
the driers, but became very brittle on drying, doubtless due to the 
large amount of woody shives present. It was apparent that more 
wood must be removed from the finished product. This could be ac¬ 
complished by removing it from the straw before treatment, or by 
more severe chemical treatment, or by a harder beating and washing. 
Another test was made on the same lot of straw, which gave a sieving 
loss of 35 per cent of the original straw. 

Other bleaches .—Three bleaches. Nos. 202, 203, and 204, were made, 
similar to bleach No. 193, using 14.7 per cent of lime and treating 
10 hours at 160° C., equivalent to 60 pounds steam pressure. 

The stock from bleach No. 202 was beaten and washed eight hours 
in a 400-pound beater, following the roll down fairly hard. At this 
point the stock was removed and weighed, giving a yield of 63.8 
per cent of the sieved straw, or 41.5 per cent of the original bone-dry 
straw. 


UTILIZATION OF AMERICAN FLAX STRAW. 


13 


Stock from bleaches Nos. 203 and 204 was beaten and washed 
hours, after Avhich the washed stock from bleach No. 202 was added 
and the whole beaten and washed for 18 hours. The feeling and 
appearance of the stock improved during the whole beating and 
washing period, but it was still apparent that not enough wood was 
being removed. Competent employees judged that there were 250 to 
300 pounds of stock in the beater at this point, which would represent 
a yield of 40 to 47 per cent of the sieved straw, or 26 to 30^ per cent 
of the original dry weight of straAv. 

The stock Avas sized Avith 1 per cent of size and 3 per cent of 
alum and run oa er the Fourdrinier paper machine at a speed of 91 
feet per minute. The stock acted A^ery aa ell on the machine, but, as 
in the previous test, the sheet became brittle on drying. It was 
evident that a still harder or different bleach was necessary or that 
the manner of beating and washing should liaA’e been different. 

MILL TESTS ON THE MANUFACTURE OF FIBER BOARD. 

When the experimental Avork on the utilization of flax straw in 
the manufacture of paper had reached this point, there was a great 
uneasiness in the fiber-boavd industry concerning the supply of 
foreign raAv material because of the outbreak of the European 
Avar. As previously noted, there are imported into the United States 
annually about 7,000 tons of flax Avaste derived from the foreign tex¬ 
tile industries, Avhich are used almost exclusively in the manufacture 
of the counter-board grade of fiber boards. These counter boards 
are used chiefly for the manufacture of counters and toes for the 
stiffening of the heels and toes of shoes. 

The price of this flax Avaste has ranged from $25 to $29 per ton 
from 1908 to 1912, inclusive, and the aAwage price in 1913 was $36.50. 
The Avaste had been constantly deteriorating in (piality, until the same 
grade Avas 20 to 25 per cent poorer for fiber-board manufacture than 
in 1908-9. Soon after Avar Avas declared the available supply of flax 
Avaste Avas bought up and stored for future manufacture, and the 
importations were greatly curtailed. Finally, the Avaste Avas Avith- 
draAvn from quotation, after reaching prices of about $65 per ton. 

It Avas thought that if American flax straAV could be substituted for 
the imported Avaste, this Avould be the most propitious time to induce 
manufacturers to cooperate in the Avork and establish a market for 
this crop Avaste. One of the leading counter-board factories signi¬ 
fied its Avillingness to cooperate in the project and kindly placed 
at the disposal of the Bureau of Plant Industry many of its regular 
machines and its semicommercial testing equipment. 

The semicommercial testing equipment consisted of a direct steam, 
iron, rotary bleach boiler, about 2 feet in diameter by 5 feet in length; 


14 


BULLETIN 322, U. S. DEPARTMENT OF AGRICULTURE. 


a 10-poiind washing and beating engine; and a Avet machine capable 
of producing board sheets 15 by 22 inches. 

After several preliminary tests on the small machines it was found 
that flax straw bleached Avith 14 j^er cent of lime for 15 hours at 170° 
C. and Avashed and beaten in the regular manner made a board Avhich 
Avas almost invariably too hard and brittle, but if used aa ith an equal 
amount of bleached old mixed string and an equal amount of bleached 
board cuttings a satisfactory board could be made. Still there Avas 
usually a little too much brittleness. 

Test No. 115 .—A test Avas then made, designated as No. 115, using 
the large beater and Avet machine. Tavo charges of 255 pounds each 
were made in a rotary pulp boiler, bleaching Avith 14 per cent of 
burned lime at 170° C. for 15 hours. About 275 pounds, dry Aveight, 



Fig. 4.—Fiber-board press or calender. 


of this stock Avas charged into a 700-pound beater and Avashed and 
beaten Avith a hard brush for 2^ hours, after Avhich the roll Avas raised 
and the Avashing continued one hour longer. The Avood Avas reduced 
and remoA^ed to a considerable extent, and, although the bast fiber 
Avas reduced in length someAvhat, there Avas no bast-fiber loss in the 
Avash water. At this point the Avorkmen pronounced the stock A^ery 
similar in appearance and action to that from flax Avaste. 

The Avashed flax Avas then added to a beater containing an equal 
Aveight of bleached mixed strings, Avhich had been Avashed and beaten 
for seA^en hours, and an equal Aveight of bleached board cuttings Avas 
added. The furnish therefore aa as one-third mixed strings, one-third 
flax straAv, and one-third board cuttings. This charge Avas beaten 
doAvn, sized, and loaded by the experienced beatermen of the com¬ 
pany in the equivalent of 12 hours total time. The stock Avas run 
into board on a regular 44-inch wet machine and dried in the loft 




UTILIZATION OF AMERICAN FLAX STRAW. 


15 


for 15 hours, after which it was put through the board calender 
(fig. 1). 

The thin or light-weight sheets were too soft, those of medium 
weight satisfactory, and the heavy ones a little too brittle. It should 
be stated that the stock needs to be reduced to dilferent fiber lengths, 
depending on the weight of board desired. Those boards of this test 
which were of medium weight and were satisfactory were sold with 
the company’s i*egular stock and no complaint was received from them. 

Test So. 118 .—A test was then made, using the large beater and 
regular wet machine, employing the same furnish as in test No. 115, 
but the charge of mixed strings was added unwashed to the charge 
of fiax straw, which had been washed for 3 hours. This combined 
charge was washed for 11 hours more, when the furnish of board 
cuttings was added and the charge sized, loaded, and beaten off in a 
total of 11 hours, or 11 hours after the addition of the strings. The 
board was tough, but much too soft. The old saying that “ the paper 
is made in the beater ” seems to apply equally well to fiber-board 
manufacturing, as the furnish in this test was the same as in test 
No. 115 and the difference in the method of furnishing was in¬ 
sufficient to account for the difference in the two products. 

Test Xo. 125 .—A test on the large mill machines was now made, 
including the bleaching in the company’s large bleach boiler. Three 
thousand pounds of the baled straw were pitched over carefully 
with fine pitchforks and freed from chaff, which amounted to 33 
per cent of the original straw. The 2,000 pounds of sieved straw 
were charged into the boiler, together with 14 per cent of burned 
lime and 800 gallons of water. The charge was heated by direct 
steam to 105 pounds pressure in 1^ hours and maintained at this 
pressure for 15 hours, after which the pressure Avas relieved in IJ 
hours and the charge removed. For some reason the stock did not 
appear quite as well reduced as Avas the bleach carried out under the 
same conditions in the smaller boiler at Cumberland Mills, Me. 

A 500-pound beater furnish of one-third domestic flax straw, 
one-third mixed strings, and one-third board cuttings and sulphite 
screenings Avas washed and beaten in the folloAving manner: The 
fiax-straAV stock Avas first washed in the beater for 5 hours, Avhen 
the mixed-string stock was added, after having been washed for 1^ 
hours. The charge Avas beaten 4 hours, Avhen the one-third of board 
cuttings and sulphite screenings Avas added and the Avhole beaten 
G hours more. The furnish was sized and loaded in the regular 
manner. This stock was run over a 44-inch Avet machine, loft dried, 
and calendered, giving a board Avhich, although not perfectly satis¬ 
factory, Avas readily used in the trade. 

It AA’as realized at this point by the officials of the Department of 
Agriculture and the fiber-board manufacturing company that the 


16 


BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 



liax straw contained a fiber which was very promising for this line 
of product, but the woody portion was so high that it ofiset to a 
large degree the desirable quality of the bast fiber. 

FLAX TOW IN THE FIBER-BOARD INDUSTRY. 

CONDITION OF THE FLAX-TOW SUPPLY. 

Field work in Minnesota and North Dakota, which was under¬ 
taken after these tests were made, developed many factors of direct 
and immediate value to this project and to the paper and fiber-board 
industry in general. 


Pig. 5.—A carload of flax upholstering-tow bales. 

Of the total quantity of unused flax straw resulting from the 
thrashing of the flax crop, fully 90 per cent is actually burned in the 
fields. Farmers located near tow mills are able to sell all of their 
straAv, getting in some sections $2.50 to $3.50 per ton, loose, hauled 
to the mill. In one section farmers were selling at $1 per ton in the 
stack. In those sections where flax is raised more abundantly, such 
as central and western North Dakota, it is the general belief that 
the baled straw can be delivered f. o. b. cars in large quantity at not 
more than $4 per ton. (Figs. 5 and 6.) 

About the only profitable use to which the straw is put is in the 
manufacture of flax tow, which is consumed for the most part in up¬ 
holstering and as a packing material for crockery, glassware, etc. 
This toAv is made from tangled and broken flax straw after it has 





UTILIZATION OF AMERICAN FLAX STRAW. 


17 


been thnished in ordinary grain-thrashing machines, without retting, 
and is very different in character from the flax tow of the spinning 
mills. A comparati^'ely small quantity is manufactured into insulat¬ 
ing boards, such as are used in building construction and refrigerator 
cars; also a very small amount is used in the manufacture of rough 
twine. There are about 10 flax-tow mills in the flax region, the 
largest of which consumes over 30,000 tons per year, while some use 
not more than 1,000 tons. 

The flax-tow machines consist essentially of a series of corru¬ 
gated rollers operating in pairs under considerable pressure, through 
which a uniform layer of straw is rolled. The woody portion is 
crushed and broken into small pieces, which fall away between the 
rolls and are further removed by dusting and screening devices. 



Fig. 6.—A truck load of flax upholstering-tow bales. 


Flax upholstering tow is sold under four grades and normally in 
carload lots at the following prices: Coarse, $10; medium, $18; fine, 
$24; extra fine, $32. These prices were the quotations in September, 
1914, for baled flax tow, f. o. b. St. Paul, Minn., at which point flax 
straw can be bought at $7 per ton, baled, in carload lots. The dif¬ 
ferent grades vary in the amount of woody matter removed and the 
degree of softness of the tow (fig. 7). 

Considering these prices of tow, the amount of wood removed, 
and the general physical condition of the material, it would seem 
that tow would be a more desirable as well as a more profitable raw 
material than straw for the fiber-board manufacturer, if not indeed 
for the paper manufacturer. In the case of medium tow, for example, 
2 tons of straw are required to make 1 ton of tow, which is a considei- 





18 BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 

able item where the material must be shipped east to the board and 
paper mills, as most of the counter-board mills are in or near New 
England. It is also a considerable item when it is recalled that the 
board and paper manufacturer must remove more or less (and in 
some cases practically all) of the wood during the manufacturing 
process before a pulp is obtained suitable for his purpose. More¬ 
over, the physical condition of the material is such that it is more 
amenable to chemical pulping processes, yielding to less expensive 
processes and producing a more uniform and satisfactory product. 

MILL TESTS ON THE MANUFACTURE OF MEDIUM FLAX TOW. 

On account of previous and satisfactory laboratory results on flax 
tow and because of the satisfactory condition of the tow industry 
near the flax region, it was decided to be advisable in continuing 
board tests to employ flax tow instead of flax straw, as had been done 
up to this time. With this in view, a cooperative test was made in 



Fig. 7.—Small samples of flax straw and tow. From right to left: Straw, coarse tow, 
medium tow, fine tow, and extra fine tow. 


a large tow mill at St. Paul, Minn., in which 24.8 tons of straw 
were manufactured into 14.7 tons of medium tow, or 59.3 per cent of 
the original straw, which yield is believed to be somewhat higher than 
that obtained in ordinary practice. The bales average 100 pounds, 
and 15 tons can be loaded into a car. This lot of tow was shipped to 
a counter-board mill in Maine, Avhere cooperative board tests were 
made later, while four bales were sent to the Washington laboratory 
for preliminary tests as to the most suitable method of treatment. 
From observations made during this tow test, it was evident that by 
very slight modifications of the tow machinery considerabW more 
woody matter could be removed, greatly to the advantage of the paper 
manufacturer. 

I.ABORATORY TESTS ON THE TREATMENT OF MEDIUM FLAX TOW. 

The tow used in these tests was that manufactured at St. Paul, 
as previously described. In order to obtain an idea of the amount 
of loose woody matter still remaining in the tow, a weighed quantity 
was shaken out lightly by hand, yielding 16 per cent of woody shives. 
These shives are of no value to the paper or board manufacturer, and 





UTILIZATION OF AMERICAN FLAX STRAW. 19 

it is believed that they can be remoA’ed readily at the tow mills at a 
very slight increase in the cost of processing the tow. 

A series of lime cooks or bleaches was made in the laboratory, em¬ 
ploying a 38-liter rotary pulp boiler operated by direct steam, from 
the results of which it was concluded that a treatment with 14 per 
cent of burned lime for 4 hours at a steam pressure of 100 pounds 
l^er square inch would giA^e a product satisfactory for fiber-board 
manufacture. Under this treatment, the yield of washed or sepa¬ 
rated fiber was 48 per cent of the bone-dry weight of tow used. 

Table VI gi^-es a partial list of the laboratory bleaches, illustrat¬ 
ing the method of determining the correct amount of lime necessary 
to be used. 


Table A^I. —List of hleaches, shotvmg the method of determining the correct 

amount of lime to be used. 


Cook No. 

Lime 

Time of 
treat¬ 
ment. 

Pressure 

per 

AVaste liquor (per liter). 

used. 

square 

inch. 

Acidity. 

Soluble 
lime salts. 

246. 

Per cent. 
12 

Hours. 

5 

Pounds. 

100 

Grams, acetic 
acid. 

0.97 

Grams,CaO. 
6.8 

247. 

14 

5 

100 

.26 

5.8 

248. 

15 

5 

100 

Per cent,CaO. 
0.008 

6.3 

249. 

17 

5 

100 

.023 

6,9 

250. 

17 

. 5 

100 

.024 

7.2 




The yield on cook No. 250 was 73.8 per cent of total fiber and 48.6 
per cent of washed or separated fiber. Washing was done in the 
beater by means of a regular Avasher covered with 30-mesh wire 
cloth, such as is used in fiber-board mills. 

A series of bleaches on flax straAv is recorded in Table VII, 
shoAving the extent to which fiber can be injured by not employing 
sufficient lime in the bleach. 


Table VII. —List of bleaches, showing the extent of injury to fiber through 

insufficient lime. 


Cook No. 

Lime. 

used. 

Time of 
treat¬ 
ment. 

Pressure 

per 

square 

inch. 

AVaste liquor 

Acidity. 

per liter). 

Soluble 
lime salts. 

Tensile 
strength of 
ultimate 
fiber per 
square mm. 
of solid 
cross 
section.! 





Grams, acetic 




Per cent. 

Hours. 

Pounds. 

acid. 

Grams,CaO. 

Grams. 

‘> 4 “? . 

12 

6 

100 

2.11 

7.4 


244 . 

14 

6 

100 

.97 

9.1 

57,000 

245. 

16 

6 

100 

( 2 ) 

7.0 

65,000 





Per cent, CaO. 




18 

6 

100 

0.006 

7.0 


252. 

18 

6 

100 

.03 

7.5 

85,000 


I Determined by a method devised by this laboratory. 2 Barely alkaline. 







































20 BULLETIN 322_, U. S. DEPARTMENT OF AGRICULTURE. 

Fiber-board manufacturers would do well to pay more attention to 
the reaction of their waste liquors. A few drops of 1 per cent phe- 
nolphthalein in 50 per cent alcohol dropped into about a quarter of an 
ounce of the waste liquor should produce an intense red color at once. 

MILL TESTS ON THE MANUFACTURE OF FIBER BOARD. 

Fiber-board mill tests were again undertaken in a fiber-board mill 
in Maine, but fiax tow was used instead of the straw that was 
employed in the previous work. The regular machines were used 
in all of these tests and the work was performed by the regular mill 
employees; in other words, the flax tow was subjected to actual com¬ 
mercial manufacturing conditions, although in some of the tests 
slight changes in procedure were made, as will be shown. 

Bleach No, 2SJ ^.—A charge of 4,062 pounds was treated with 14.6 
per cent of burned lime by slaking 578 pounds of the lime in 1,600 
gallons of water in the bleach boiler, then adding the charge of tow. 
Direct steam was admitted, and the pressure was brought up to 110 
pounds in 3 hours and maintained for 4 hours, after which the 
pressure was relieved in 2 hours and the charge dumped. 

After remaining on the drain floor over night this stock was 
made into a 500-pound beater furnish of one-third flax tow, one- 
third mixed strings, and one-third board cuttings, in the following 
manner: The mixture of tow and mixed string was washed in the 
beater for 2 hours, when the board cuttings and sulphite screenings 
were added and the charge beaten off in a total of 12 hours. Near 
the end of the beating, the filler, color, and size were added. This 
stock was run over a 44-inch wet machine, loft dried, and put 
through the board calenders. The wet boards from the wet ma¬ 
chines measured 38 by 44 inches, and after they were dried and 
calendered they measured 33 by 44 inches, which is about the correct 
amount of shrinkage. These boards were sold in the trade, but not 
as counter boards, as they were too brittle for that grade. The 
brittleness was due, according to the management and employees, 
to the fact that the stock was beaten too short. In working with 
any new material, its characteristics and differences must be learned 
before its full possibilities can be developed, and many failures must 
be expected during the earlier stages of development. 

Bleach No. 235 .—This bleach was made in the same manner as 
No. 234, but 15 per cent of lime was used and the charge cooked 
at a steam pressure of 75 pounds for 9 hours, the total time of cook¬ 
ing being 12 hours. The stock from this bleach was used in the 
same furnish and manner as that of bleach No. 234. This furnish 
was beaten off in a total of 12 hours, loaded, colored, and sized, as in 
the previous test. The stock showed up very well in going over the 
wet machine, giving a board measuring 38 by 44 inches wet, which 
after loft drying and calendering measured 33 by 44 inches. This 


UTILIZATION OF AMERICAN FLAX STRAW. 


21 


board was pronounced by the fiber-board employees and the man¬ 
agement officials to be equal to those boards of this class in which 
imported flax waste is used, and it was sold on the market bv the 
cooperating mill as a second-grade counter board at the regular 
price of such boards, namely, 5 to 5^ cents per pound (fig. 8). 

The thin boards of this run were somewhat soft and the thick 
boards were somewhat brittle, which naturally would be the case, 
since each thickness of board requires that the stock be beaten ac¬ 
cordingly. 

Additional tests .—Three other complete tests were made like the 
two above recorded, and although the results were not as satisfactory 
as those of No. 235, the board was sold as second-grade counter board 
and no complaint has been received from it. 



Fig. 8.—A package of counter boards, in the manufacture of which domestic flax 
upholstering tow was employed in place of imported flax waste. Size of boards, 

33 by 44 inches. 

Unfortunately, no methods of testing boards have been devised 
which give the results as a numerical expression, the usual method 
being to bend and fold the board with the fingers in different man¬ 
ners, according to the use to which the board is to be employed, and 
noting the degree with which it breaks or cracks. 

YIELD OF PRODUCT AND COMPARATIVE COSTS. 

It is impossible in the mill tests to determine the yield of washed 
or available fiber derived from the straw and tow, even as compared 
with imported flax waste. The general opinion of the management 
and employees who followed the tests was that there was no ap¬ 
preciable difference in yield so far as could be determined by observa¬ 
tion during the tests. 

Laboratory determinations of the yield of washed fiber on 6-pound 
samples of flax straw, medium flax tow, and the best grade of im¬ 
ported flax waste gave the results shown in Table VIII. 











22 BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 


Table VIII. —Yield of icashed fiber from flax straw, medium tow, and vnported 

flax leaste. ^ 


Material tested. 

Lime 

used. 

Time of 
treat¬ 
ment. 

Pressure 

per 

square 

inch. 

Yield of 
washed 
fiber. 

Flax straw. 

Per cent. 
18 

Hours. 

6 

Pounds. 

100 

Per cent. 
41.2 

Medium flax tow. 

17 

5 

100 

50.4 

Imported flax waste. 

10 

10 

45 

55.7 



It should be remembered that these are experimental results, and 
although necessarily they do not represent the mill yields, they are 
strictly comparative. Probably the yields are lower than those in 
mill practice. Although domestic flax tow yields a lower percentage 
of washed fiber than does imported flax waste, the lower price paid 
for the former makes the total cost of the washed product made from 
domestic tow delivered as far east as Boston very little more than 
the total cost of washed fiber produced from imported waste. It would 
thus appear that, so far as both cost and qualit}^ of i)roduct are con¬ 
cerned, the domestic flax tow from the region of the Dakotas can 
compete against imported flax waste in the manufacture of counter 
boards even if the manufacture is conducted as far east as Boston. 
If the board manufacture is conducted near the flax region, the 
results would be about as 7 to 5 in favor of domestic tow. 

SUGGESTIONS FOR FLAX FARMERS. 

Many letters have been received from the farmers of the flax region 
asking for information in regard to the profitable disposal or utiliza¬ 
tion of their Avaste flax straw. 

So far as its use in the paper industry is concerned, it is obvious 
that no immediate benefit can be derived until its value in this line 
is proA^ed and industries are established wdiich will create a market 
for it. The success of the project depends to a certain extent upon 
the farmer. The price of his straw must net him a fair profit, but 
at the same time this price must be such that the material will be 
attractiA^e to the paper manufacturer. When the time comes that 
the paper industry will be in a position to use this material the flax 
farmer should have made arrangements to supply the material in 
such a manner that he may secure his proper proportion of the bene¬ 
fits and profits. 

It would seem, from the paper-maker’s as Avell as the farmer’s 
standpoint, that the most beneficial and profitable as well as generally 
satisfactory method of assembling this material for the market Avould 
be to establish a number of small toAv mills throughout the region 
Avhere the most flax is grown rather than to establish a smaller num¬ 
ber of larger tow mills. This method would render more material 
available, benefit more farmers, and place the product on the market 
at a lower price. 













UTILIZATION OF AMERICAN FLAX STRAW. 


23 


As a suggestion for consideration, farmers may find it advisable to 
act cooperatively. For example, the farmers within a 5-mile radius 
might own and operate a tow mill of sufficient capacity to market the 
entire quantity of straw within their area. Under this system the 
farmer not only would benefit by the sale of his straw but would re¬ 
ceive also a profit from the manufacture of the tow. 

From present indications it appears that different grades of tow 
should be produced for the paper industry, depending on the grade 
of paper to be manufactured. For example, a medium grade of tow 
might answer the requirements of the board manufacturer, while a 
fine or extra fine grade would be required by the wrapping-paper 
manufacturer. Investigation doubtless will be continued along the 
wrapping-paper and writing-paper lines, in order to develop a market 
which will absorb an appreciable amount of this large and potentially 
valuable crop waste. 

CONCLUSIONS. 

Should flax straw or tow prove to be of value to the paper or board 
industry, the condition of the raw-material market at the present 
time is such that the new supply would be very welcome to the trade. 
Since this work was undertaken, many calls for information have 
been received from the mills and many offers of cooperative help 
have been extended, which show conclusively the attitude and needs 
of the industry. 

If, as seems very probable, domestic flax straw or tow can replace 
imported flax waste in the manufacture of counter boards, it should 
open up a market for about 20,000 tons of straw, which, although a 
small amount, is a step in the direction of the advancement of home 
industry. 

Should the straw be able to compete successfully in the manufac¬ 
ture of writing papers it should open up a market of between 200,000 
and 400,000 tons of straw per annum, the sale of which would repre¬ 
sent an added revenue to the flax region of $800,000 to $1,600,000. 
This country is importing over $2,000,000 worth of rags per annum, 
which are used largely in the manufacture of writing papers. 

The wrapping and bag paper lines offer like possibilities, which 
are worth consideration in this general project. 

The flax crop, which furnishes normally $33,000,000 worth of flax 
seed, yields about 1,400,000 tons of straw, which is put to no profitable 
use and for the most part is burned in the fields. It is purely a waste 
product and, moreover, one which is already assembled to a large 
degree. It has always been a migratory crop, but increased knowl¬ 
edge of its nature and proper methods of raising are beginning to 
check this condition. Moreover, if the flax farmer who realizes $12 
per acre for his seed can deliver his straw at tow mills or other cen¬ 
tral points for, say, $4 per ton, he is realizing an increased revenue 


LIBRARY OF CONGRESS 



0 018 534 984 6 


24 BULLETIN 322^ U. S. DEPARTMENT OF AGRICULTURE. 


per acre of 25 per cent, which fact also will exert a restraining 
tendency on the migration of the crop. 

Of this large crop waste, 91 per cent is raised in the following 
States: North Dakota, 43.7 per cent; Minnesota, 16.1 per cent; South 
Dakota, 15.7 per cent; and Montana, 15.3 per cent. From the total 
of 1,600,000 tons of flax straw not over 200,000 tons are put to a 
profitable use in the manufacture of flax tow and insulating material. 
Many fruitless attempts to utilize this straw in paper manufacture 
have been made, but thus far no permanent industries have resulted. 

In the manufacture of fiber counter boards used in shoe manufac¬ 
ture, there are used annually about 7,000 tons of flax waste imported 
from Europe. Since the outbreak of the European war the importa¬ 
tion of this material has been curtailed and its price has advanced 100 
per cent. For these reasons, among others, the Department of Agri¬ 
culture has investigated the adaptability of domestic flax for supply¬ 
ing this market. As the result of laboratory and commercial co¬ 
operative tests in a counter-board mill, counter boards were pro¬ 
duced, employing domestic flax tow in place of imported flax waste, 
which were pronounced satisfactory and were actually sold by the 
mill to the trade for counter manufacture at the regular price of 
counter boards, namely, 5 to 5J cents per pound. 

Flax tow manufactured in the flax region can compete more suc¬ 
cessfully than can flax straw with imported flax waste, and, as all 
counter board is of eastern manufacture, it would seem logical to 
consider its manufacture near the source of flax-straw supph^ and 
near the large and increasing Middle West market. The farmer in 
the flax regions would then be situated most favorably for the 
marketing of his flax straw. 

It is realized that this source of utilization would open a market 
for not over 20,000 tons of straw annually. It is proposed, therefore, 
to extend this investigation into the lines of wrapping and writing 
paper manufacture. If successful methods of so using flax straw and 
tow are discovered, a large proportion of this great and potentially 
valuable crop waste could be utilized. This not only would beneflt 
the farmer but would exert a very strong tendency toward maintain¬ 
ing the flax crop in our system of agriculture. 

The attention of the Department of Agriculture has been called 
repeatedly to various schemes which have been promoted by indi¬ 
viduals and organizations in attempts to lead the farmer to believe 
that there are demands for flax straw greater than careful investi¬ 
gation has shown to exist. The farmer is advised, therefore, to in¬ 
vestigate carefully any schemes which have not been thoroughly 
tested and found to be of practical value by reputable manufacturers. 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1915 






